The Half fluence PDT protocol for CSC was performed using half the normal duration of verteporfin laser time (Visudyne, Novartis AG, Bülach, Switzerland) All patients received a bolus infusion of 6 mg/m2 body surface area over 1 minute. Patients were assigned to treatment protocols, using a fluence of 25 J/cm2. In the 25-J/cm2 group, patients received an irradiance of 600 mW. Depending on the irradiance, the time of photosensitization was 42 seconds. A total light energy of 25 J/cm2 over 42 seconds was delivered to the area of choroidal hyperperfusion as observed in ICGA instead of the angiographic leakage sites shown in FA. Only the area of choroidal vascular abnormality that was supposed to cause the serous detachment involving the macula was considered to be treated. To avoid overtreatment on the choroidal vasculature in causing choroidal ischemia, the laser spot size was set at a maximum of 4,500 µm. This restriction in laser spot size is adequate, from our previous report, to reverse the serous macular detachment by reducing the choroidal extravascular leakage and sub-RPE hydrostatic pressure at the macular area. In patients with bilateral CSC, only one eye was recruited for the study, and the eye with thicker central retinal thickness on OCT was chosen. After treatment, patients were given protective spectacles and instructed to avoid strong light for 3 days.